Method for managing one or more print processing queues

ABSTRACT

A method of ordering print jobs in a print queue is provided. The method includes storing one set of print jobs in the print queue, and processing the one set of print jobs with a cell (having one or more print processing devices) and a first print job sequencing rule dictating a first print job sequence. Another set of print jobs is stored in the print queue, and processing of the other set of print jobs with both the cell and the first sequencing rule is simulated to obtain a first print job processing indicator. Additionally, processing of the other set of print jobs with both the cell and a second print job sequencing rule, dictating a second print job sequence, is simulated to obtain a second print job processing indicator. The first print job processing indicator is compared with the second print job processing indicator, and, based on the comparison, the other set of print jobs is processed with either the first print job sequencing rule or the second print job sequencing rule.

BACKGROUND AND SUMMARY

The disclosed embodiments relate generally to a method for operating aprint processing system and, more specifically, to a method for managingone or more print processing queues by dynamically setting jobsequencing rules in accordance with conditions to which the printingsystem is being subjected.

Conventional print shops typically are organized in a fashion so thatrelated equipment is grouped together. For example, printing equipmentmay be grouped and located together, while finishing equipment may begrouped and located in another location. Thus, the print shop may be setup to have a printing department, a finishing department, and otherdepartments corresponding to the type of process or operation that isperformed within that department. The organization of a print shop istypically often independent of print job complexity, print job mix andtotal print job volume.

When a new print job arrives, the print job sequentially passes througheach department until the print job is completed. The conventionalapproach can lead to significant time delays, as well as increasedwork-in-progress and inventory costs.

In accordance with an improved approach, a print shop may be reorganizedinto autonomous cells as disclosed in U.S. Pat. No. 7,079,266 to Rai etal., the pertinent portions of which are incorporated by reference. Foreach autonomous cell in a corresponding group, resources (e.g.,equipment or stations) are grouped together according to different jobclasses commonly encountered by a specific print shop.

In the type of print shop contemplated by the '266 patent, print jobs(requiring one or more print processing related operations) arecommunicated to the print shop for handling by one or more autonomouscells. Prior to communicating the jobs to the one or more cells, aserver is used to schedule processing of the jobs (or portions thereof)at the one or more cells. Scheduling systems suitable for use in a givenprint shop environment are disclosed in U.S. Pat. No. 7,051,328 to Raiet al. and U.S. Pat. No. 7,065,567 to Squires et al.

U.S. Pat. No. 7,051,328 discloses a print workflow including a workflowmapping module that determines a workflow of one of several documentprocessing jobs for processing. A job description module may be used tosplit at least some of document processing jobs into sub-jobs forprocessing by the printing devices in the cells. Additionally, a printcell controller, at any one of the cells for receiving at least onesub-job, can be used to further split a sub-job into lots for processingamong devices in a given cell. The printing workflow system of the '328patent permits distribution of document processing jobs throughout anetwork environment.

The '328 patent further discloses a method of assigning sub-jobs toavailable cells in a priority workflow system for printing aproduct-type. The method includes identifying the maximum capacity ofthe available cells to print the product type. The current capacity ofeach of the available cells to print product type is also identified.Based on the maximum capacity and current loading of each of theavailable cells, a current capacity of each of the available cells forprinting the product-type is determined. At least one of the availablecells is assigned for printing.

U.S. Pat. No. 7,065,567 discloses a system for scheduling adocument-processing job in a printing workflow system. The schedulingsystem includes first and second modules for determining whether thedocument processing job in a printing workflow system can be processedby one or by a plurality of cells, and determining the time it wouldtake to process the document processing job in the first module. Thescheduling system includes a third module for determining timingparameters to accomplish the document-processing job based on theinformation in the second module. The scheduling system includes afourth module for applying the timing parameters to one or more cells toprocess the document processing job by a specified due date. Finally,the scheduling device includes a fifth module for queuing the documentprocessing job in one or more cells based on the information from thefourth module to efficiently process the document processing job by thespecified due date.

The pertinent portions of all of the above-mentioned patents areincorporated herein by reference.

U.S. Pat. Nos. 7,051,328 and 7,065,567 appear to contemplate ascheduling approach in which job sequencing rules used by acell-controller are fixed for a corresponding print shop. These aredetermined by an assessor who simulates a set of jobs (using a suitableassessment tool) and determines which rule(s) best meets therequirements of the print shop. Examples of known print job sequencingrules include, among others, “Least Slack Time (LST),” “Earliest DueDate (EDD),” “Shortest [Remaining] Processing Time (SPT),”First-In-First-Out (FIFO),” “Last-In-First-Out (LIFO)” or “MaximumProcessing Time (MPT).” It has been found that assigning one or more jobsequencing rules to a set of queues in a fixed manner can, during giventime intervals, lead to degraded shop performance since theeffectiveness of at least some rules, based on various factors, canchange significantly. For instance, at one utilization level a FIFO rulemay result in very acceptable job turnaround for a given cell, while atanother utilization level, the job turnaround for the same cell may bewholly unacceptable. Accordingly, it would be desirable to provide amethodology that permits a print shop to dynamically adjust jobsequencing rule usage across cells so as to optimize cell processingcapability.

In one aspect of the disclosed embodiments there is disclosed a methodof ordering print jobs in a print queue. The print queue is operativelyassociated with a cell having one or more print processing devices forprocessing print jobs. The method includes: (A) storing a first set ofat least two print jobs in the print queue; (B) corresponding a firstprint job sequencing rule with the print queue, the first print jobsequencing rule dictating a first print job sequence in which the firstset of at least two print jobs are to be processed; (C) processing thefirst set of at least two print jobs with the cell in accordance withthe first print job sequencing rule; (D) storing a second set of atleast two print jobs in the print queue; (E) performing simulations todetermine if the second set of at least two print jobs should beprocessed in accordance with the first print job sequencing rule or asecond print job sequencing rule, the second print job sequencing ruledictating a second print job sequence in which the second set of atleast print jobs are to be processed, wherein the first print jobsequence is different than the second print job sequence; (F)determining, with said simulations of (E), whether the second set of atleast two print jobs should be processed in accordance with the firstprint job sequencing or the second print job sequencing rule; and (G)when it is determined that the second set of at least two print jobsshould be processed in accordance with the second print job sequencingrule, changing the correspondence of the print queue from the firstprint job sequencing rule to the second print job sequencing rule.

In another aspect of the disclosed embodiments there is disclosed amethod of ordering print jobs in a print queue. The print queue being isoperatively associated with a cell having one or more print processingdevices for processing print jobs. The method includes: (A) storing oneset of at least two print jobs in the print queue; (B) processing theone set of at least two print jobs with the cell and a first print jobsequencing rule, wherein the first print job sequencing rule dictates afirst print job sequence in which print jobs stored in the print queueare to be processed; (C) storing another set of at least two print jobsin the print queue; (D) simulating processing of the other set of atleast two print jobs in the cell with the first sequencing rule toobtain a first print job processing indicator; (E) simulating processingof the other set of at least two print jobs in the cell with a secondprint job sequencing rule to obtain a second print job processingindicator, wherein the second print job sequencing rule dictates asecond print job sequence in which print jobs stored in the print queueare to be processed, and wherein the first print job sequence isdifferent than the second print job sequence; (F) comparing the firstprint job processing indicator with the second print job processingindicator; and (G) based on said comparing of (F), processing the otherset of at least two print jobs with the cell in accordance with one ofthe first print job sequencing rule and the second print job sequencingrule.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram illustrating a print workflow system incombination with cells and their corresponding devices;

FIG. 2 is a block diagram including software components employed in theprint workflow system of FIG. 1;

FIG. 3 is a block diagram of a server employing the printing workflowsystem of FIG. 1;

FIG. 4 is a block diagram illustrating how the print workflow system isused to accommodate the splitting of a document processing job intosub-jobs;

FIG. 5 is a block diagram illustrating a capacity of a cell;

FIG. 6 is a block diagram illustrating some capabilities of a cell;

FIG. 7 is a block diagram illustrating an approach for routing jobs tocells by way of a corresponding series of queues;

FIG. 8 is a schematic view of one of the job queues of FIG. 7 over twomoments in time;

FIG. 9 is a flow diagram illustrating an approach for performing jobprocessing simulations to dynamically assign job sequencing rules acrossthe queues of FIG. 7;

FIG. 10 is a schematic view of a discrete-event simulation model for aproduction environment in which coil bound books are produced; and

FIG. 11 is a schematic view of a simulation model for studying theimpact of real-time controls on performance in the presence of randomvariability.

DESCRIPTION OF DISCLOSED EMBODIMENTS

The disclosed embodiments contemplate the use of a lean productionprocess server (LPPS) for coordinating production of document processingjobs in a document factory (such as a print shop). The server exploitslean production techniques to control document processing jobs. Theserver can be run on a number of different platforms, including but notlimited to, UNIX and Windows (“UNIX” is a registered trademark of theOpen Source Group, while “Windows” is a registered trademark ofMicrosoft Corporation) based-platforms. The server determines workflowpriorities and manages workflow accordingly. Those skilled in the artwill appreciate that the presently disclosed embodiments may also bepracticed with platforms that run other varieties of operating systems.Moreover, the server need not run on a dedicated computer system butrather may run on another variety of electronic devices, such as aprinter, copier, etc. Workflow priorities for document processing jobscan be determined by observing the various jobs processing units.

At least one illustrative embodiment disclosed herein presumes that thedocument factory has been partitioned into autonomous cells. Each cellis a logical grouping of resources (including both equipment andmanpower) in the document factory that is sufficient for completing atleast one type of document processing job. Thus, a first cell mayinclude a printer and binder whereas a second cell may include a copierand a collator. The LPPS is responsible for distributing documentprocessing jobs among such cells in an efficient manner.

Referring to FIG. 1 a printing workflow system 2 in a print shop (i.e.,a document factory) is shown. The printing workflow system 2 controls amultitude of cells 4 through 8. The printing workflow system 2 sendsinformation to and receives information from the cells 4 through 8 viathe communication links 10. The cells 4 through 8 are comprised of atleast one device 5 for assisting in completing a document processing jobof given product-types. For example, printing device 5 could be a 600dpi monochrome printer, while printing device 7 could be a 1200 dpicolor printer.

Referring to FIG. 2, several of the software modules employed in theprinting workflow system 2 are shown. The printing workflow system 2includes a workflow mapping module 12 that determines the workflow forselected document processing jobs. The workflow, among other things,identifies the operational steps needed to complete a documentprocessing job, and the sequence in which these operational steps shouldbe performed. A job decomposition module 14 is included for splittingthe document processing jobs into sub-jobs and for sending the sub-jobsto cells for completion. A product cell controller (PCC) 16 may beprovided at given cells for receiving at least one sub-job to furthersplit the sub-job to be processed by a device in the cell. Lastly, acell assignment module 18 is provided for assigning sub-jobs to beprocessed by a cell.

In general, a print job is received, and a workflow developed for theprint job with the workflow mapping module 12. The job decompositionmodule may split the job into sub-jobs, with the sub-jobs or job thenbeing assigned to cells for completion by the cell assignment module 18.The sub-jobs may be sent to product cell controller 16 of the assignedcells, where each sub-job may be further sub divided.

Referring to FIG. 3, a server computer system 20 (i.e., LPPS) suitablefor use in the printing workflow system 2 is shown. The server 20includes a processor 22, a storage 23, communication links 26, and aninput module 24. The input module 24 is used to receive input fromvarious devices via the communications links 26. The input module 24receives the document processing jobs on behalf of the server 20. Theprocessor 22 executes the programming instructions on the server 20 tomanage document processing jobs. The server 20 stores the instructionsin the storage 23. For example, modules 12, 14, and 18 and other datamay be stored in storage 23. Module 16 may be executed on a separateserver that is particular to a cell.

Referring to FIG. 4, the printing workflow system 2, interacting with acell in a network provided in a print server is shown. The product cellcontroller 16 for the cell receives a sub-job 48 from the server 20 tobe further processed by the cell. The server 20 stores, in storage 23,the capacities and capabilities of each cell in the print shop toproduce different product-types. For example, cell 32 in the networkproduces three different types of documents and cell 40 produces twotypes of documents. (It is quite possible that two different cells canproduce similar, or even the same, document types. A document type isuniquely characterized by the sequence of processing steps to completelyfinish the document). The server 20 stores this information to determinewhich cell has the capabilities to process a document job. The capacityof each cell is also stored to determine the volume of a particularproduct-type that a cell can produce.

As stated above, the job decomposition module 14 may split a documentprocessing job into sub-jobs for transmission to various autonomouscells for processing. To the extent a cell in the network is autonomous,it can process a job completely. In the example shown in FIG. 4, adocument processing job is split into sub-jobs 48 and 50 that are sentto cells 32 and 40, respectively. The product cell controllers 34 and 42send the sub-jobs 48 and 50 to device set 36A-36C and device set44A-44C, respectively, for processing.

Referring to FIG. 5, an example of how capacity is defined for a cell inan illustrative embodiment is shown. As stated above, the printingworkflow system 2 stores the capacity of each cell. “Capacity” is themaximum volume of a particular product type that the cell can producefor a time period. For example, FIG. 5 shows capacities for 31, 33, and34 three different product types (Product A, Product B, and Product C).The printing workflow system 2 updates the capacities and makes iteasier to determine which cells should be assigned a sub-job.Capabilities are used to determine the assignment of a sub-job to acell.

Referring to FIGS. 2, 4 and 6, an example of the capabilities 39 storedfor a cell 32 is shown. Cell 32 is capable of processing variousdocument product-types A, B, C. Hence, capabilities 41, 43, and 45 arestored for cell 32. For example, if a user has a document ofproduct-type D, then cell 32 would not be the choice to accomplish theprocessing of the document because the cell 32 does not support such acapability. The printing workflow system 2, stores the capabilities foreach cell in the print shop. This allows the cell assignment module 18to examine the capacities and capabilities of the cells to determinewhich cell to assign a particular sub-job

Referring to FIG. 7, a simplified version of a job routing system, foruse with the above-described embodiments, is designated with the numeral50. As contemplated, the router 50, which communicates with a bank ofstored jobs 52, may include at least some of the job managementcapabilities associated with cell assignment module 18 (FIG. 2) and theLPPS 20 (FIG. 3). The router further communicates with a series of printprocessing related queues 54 (designated as 54-1, 54-2, . . . 54-n),which queues, in turn, are respectively operatively associated withcells 4 through 8. In accordance with the disclosed embodiment (and asdescribed in U.S. Pat. No. 7,051,328 (e.g., FIG. 12 and accompanyingtext)), a job sequencing rule (designated in FIG. 7 as “SR_(i)”) isinitially assigned to each queue.

As understood by those skilled in the art, a job sequencing rule may beselected from a number of possible approaches, such as “Least Slack Time(LST),” “Earliest Due Date (EDD),” “Shortest [Remaining] Processing Time(SPT),” First-In-First-Out (FIFO),” “Last-In-First-Out (LIFO)” or“Maximum Processing Time (MPT).” As further understood by those skilledin the art, jobs (or job portions) stored in a given queue arecommunicated to a corresponding cell in accordance with a pull releasestrategy. That is, a set of one or more jobs (or job portions) may be“pulled” from a given queue by a corresponding cell to optimize deviceusage within the cell. This pulling of jobs or job portions is referredto below as “pull release control.”

Referring to FIG. 8, a hypothetical situation is provided to demonstratethe effect of job sequencing rules one job release. Pursuant to thehypothetical, five jobs are stored in queue 54-1 at a first time (t₁),and then ordered or sequenced in accordance with a first job sequencingrule (such as SPT). The same five jobs may be sequenced in queue 54-1 ata second time (t₂), and sequenced in accordance with a second jobsequencing rule (such as EDD). As shown by the hypothetical, the orderof job release would be different for SPT than it would be for EDD. Thatis, with SPT, the second job from the left edge of the queue would bereleased first and, with EDD, the third job from the left is releasedfirst. Hence, processing sequence for a given cell may vary as afunction of the job sequencing rule assigned to the corresponding queue.

As mentioned in the Background above, while maintaining a staticassignment of a job sequencing rule may be suitable under a significantnumber of circumstances, such assignment does not take into account thepossible dynamic nature of a print shop. It has been found thatassigning job sequencing rules dynamically can accommodate for a varietyof changes in a print shop environment, such as changes in the overall“job profile” of jobs encountered by the print shop, or utilizationlevels (including device utilization and/or device user utilization)encountered by the cells 4 through 8 (FIG. 1).

Referring to FIGS. 7 and 9, an approach for dynamically assigning jobsequencing rules across queues 54 is described. The followingdescription is focused on dynamically adjusting the job sequencing rulesacross the queues 54, but in actual practice the process could beperformed for as few or as many of the queues 54 as desired. Initially,at 58 a check is performed of the router 50 to determine if there hasbeen a noticeable change in job profile. The term “job profile” refersto the collective properties of the jobs of job bank 52 that mightimpact the capability of the cells to optimally process the jobs. Forinstance, a change in average job size or job complexity could result ina change of job profile. Additionally, the check at 58 would examine theutilization encountered at each of the cells 4 through 8. Pursuant tothe check at 58, an inquiry is made at 60. If there is no change in jobprofile or cell utilization, the process proceeds to 62 where it waitsfor a selected time interval or other event to occur. The wait intervalset for 62 might vary in accordance with a variety of factors, such as aperception regarding how often the job profile and/or cell utilizationmight change over time. Such perceived changes could be ascertainedthrough use of data collected over time at the job bank 52 and/or thecells 4 through 8. It is contemplated that an “other event” couldinclude a variety of structural or functional changes in the print shop.For instance, it might be desirable to employ the process of FIG. 9shortly after reconfiguring one or more cells of the print shop.

Referring still to FIG. 9, if job profile or utilization deviates by aselected amount, an index i is initialized (at 64) for performing a jobprocessing simulation at the first cell 4 with the jobs currently storedin queue 54-1 (“stored jobs”). At 66, a first job sequencing rule(sr(1)) is selected, and the job processing simulation is performed, at68, with the stored jobs at cell 4. With query 70, processing of thestored jobs at cell 54-1 can be simulated with a plurality of jobsequencing rules. In the exemplary approach of FIG. 9, use of 70 causesprocessing simulations to be performed for the currently stored job withn rules.

Through use of 72, processing simulations across m cells (with n jobsequencing rules for each cell) are performed. As will appear from thesimulation example below, the above process permits creation of all ofthe data necessary to dynamically select optimal job sequencing rulesfor each one of cells 4 through 8. Once all of the results from thesimulations are collected (74), decisions regarding how to optimally mapjob sequencing rules across the queues 54 can be made.

Print shop simulations demonstrate that at low to mid-utilization levels(typically less than 60%), shop performance is less sensitive to thetype of sequencing rule employed. However at higher levels ofutilization, sensitivity can increase so that improper selection ofsequencing policy can result in poor performance. Furthermore, ifperformance variability is high, job sequencing rule selection mayrequire short planning horizons. Large print shops with highfluctuations at high utilizations are often found in large enterprisetransaction environments.

Referring to FIG. 10, a workflow model, including a printer and binder,is used to consider a change in utilization for a productionenvironment. In this model, the printer possesses a rated output of6,000 impressions per hour. It is assumed that, (a) jobs arrive at theprinter randomly every 2 hours, (b) the average job size is 10,000impressions, and (c) the jobs are due 15 hours from the time of arrival.The variation in the job size is modeled by an exponential distributionwith a mean of 10,000. The printer is capable of printing at a constantrate of 6.00 impressions per hour. The impact of random failures on theprinter was modeled with an exponentially varying failure distribution(having a mean time to failure of 50 hours), and an associated repairdistribution (having a mean time to repair of 4 hours). The values usedin the above-described simulation are consistent with at least someproduction print shops using a high end printing system, such as theDocuTech Publishing Printing System (“DocuTech” is a registeredtrademark of Xerox Corporation).

Referring to FIG. 11, a model developed with Arena Professional Edition(from Rockwell Software) for simulating the workflow model of FIG. 10 isshown. If the workflow model of FIG. 10 is simulated without controlsfor 20,000 hours of production time, it results in an average turnaroundtime (TAT: TAT=job completion time−arrival time) of 18.66 hours. Thevalue added time that is associated with a typical job is only 1.74hours; the rest of the time is spent by the job waiting in some queue.

Referring still to FIG. 11, a feedback control loop was added to thesystem that released jobs to the printer, and the jobs from the inputqueue were communicated to a corresponding cell with one of several jobsequencing rules (also referred to below as “scheduling policies”). Theresults from the simulation are shown below in Table 1 and Table 2.

TABLE 1 Results from simulating various control policies at highutilization levels. Turnaround Time Value Added Time (= Job Completion(i.e. Actual time the Time − Arrival job spent on the Printer SchedulingPolicy Time) hours printer) Utilization Open loop 16.46 1.67 83% withoutcontrol Least Slack First 17.62 1.66 83% with pull release controlMaximum 43.78 1.66 83% Processing Time First with pull release controlFirst In First Out 16.46 1.66 83% First with pull release control LastIn First Out 14.70 1.66 83% with pull release control Shortest 7.22 1.6683% Processing Time First with pull release control

TABLE 2 Results from simulating various control policies at lowutilization levels. Turnaround Time Value Added Time (= Job Completion(i.e. Actual time the Time − Arrival job spent on the Printer SchedulingPolicy Time) hours printer) Utilization Open loop 3.59 1.67 43% withoutcontrol Least Slack First 3.89 1.66 43% with pull release controlMaximum 4.23 1.66 43% Processing Time First with pull release controlFirst In First Out 3.66 1.66 43% First with pull release control Last InFirst Out 3.59 1.66 43% with pull release control Shortest 3.20 1.66 43%Processing Time First with pull release control

The simulation results shown in Table 2 were obtained under the sameoperating conditions as those for the results in Table 1 except that aslower job arrival rate (random arrival once every 4 hours) was used.

It is clear from the above-described example that varying real-timecontrols and scheduling policies can significantly impact systemthroughput. For example, average TAT is about 44 hours when the MaximumProcessing Time release rule is used to release jobs, and about 7 hourswhen Shortest Processing Time release rule is used to release jobs. Byway of comparison, the average TAT achieved with no scheduling is about19 hours. At the same time, the impact of real-time feedback control ismore significant at higher utilization levels.

For a given set of scheduling policies, it should be noted that TATmight vary more at one utilization than at another. For instance,referring to Table 1 above (utilization=83%), the difference between TATfor a LIFO policy and TAT for a SPT policy is 7.52 hours. By contrast,referring to Table 2 (utilization=43%), the difference between the TATfor a LIFO policy and the TAT for a SPT policy is less than an hour.With this in mind, it might be helpful to avoid policy or sequencingrule reassignment at a given queue unless the difference in TAT (or someother selected job processing related criteria, such as earliness,lateness, or percentage of early or late jobs) between the currentlyassigned policy/rule and a reassignment policy/rule candidate exceeds aselected threshold. Accordingly, referring to Table 2, if LIFO policywere assigned to a given queue and no significant change in utilizationwas expected, a reassignment to one of a number of other policies (suchas FIFO) would be unwarranted since relatively little processing timesavings could be achieved. It will be appreciated by those skilled inthe art of print shop workflow design that a wide variety of jobprocessing related criteria (other than the above-mentioned TAT,earliness, lateness, and percentage of early or late jobs) could be usedwith the disclosed embodiments for suitably gagging the adequacy ofsequencing rule assignment.

Even though the disclosed embodiments are described in the context of adocument production factory, other forms of production that are amenableto easy job splitting (such as credit card production), canadvantageously use the disclosed approach for dynamic queue management(of the type described above) to improve associated processingarchitecture. Indeed, it should now be clear that the disclosedembodiments relate to a method permitting optimal sequencing policy tobe obtained for a group cells (with their attendant correspondingqueues) by periodically simulating a current job mix across a variety ofscheduling policies for each cell to obtain an optimal scheduling policyassignment at each cell. Consequently, in contrast to at least someprior art approaches, sequencing rule assignment is dynamic so that thegroup of cells dynamically adapt themselves to changes in operatingconditions. Moreover, by monitoring a “profile” corresponding with thecurrent job mix is monitored periodically, dynamic reassignment can beachieved as substantial changes in job profile are detected.

The following features also contribute to, among other things, theimproved operability of the disclosed embodiments:

-   -   1) In one example, certain aspects of the disclosed method are        not performed until a selected condition occurs. The selected        condition may include waiting until,        -   a) a selected time interval transpires,        -   b) a first job profile (relating to, for instance, a first            job size) differs substantially from a second job profile            (relating to, for instance, a second job size),        -   c) cell utilization (including device utilization and/or            device user utilization) exceeds a selected threshold, or        -   d) a selected event (such as the addition of a cell to a            print shop or a reconfiguration of the print shop) occurs.    -   2) Job processing indicators (relating to, for instance, average        TAT, earliness, lateness, or percentage of early or late jobs)        may be compared with one another to determine which one of at        least two sequencing rules should be used in setting the        sequence of two or more jobs stored in a given queue.

The claims, as originally presented and as possibly amended, encompassvariations, alternatives, modifications, improvements, equivalents, andsubstantial equivalents of the embodiments and teachings disclosedherein, including those that are presently unforeseen or unappreciated,and that, for example, may arise from applicants/patentees and others

What is claimed is:
 1. A method of ordering print jobs in a print queue,the print queue being operatively associated with a cell having one ormore print processing devices for processing print jobs, comprising: (A)storing a first set of at least two print jobs with a first profile inthe print queue; (B) associating a first print job sequencing rule withthe print queue, the first print job sequencing rule dictating a firstprint job sequence in which the first set of at least two print jobs areto be processed; (C) processing the first set of at least two print jobswith the cell in accordance with the first print job sequencing rule;(D) storing a second set of at least two print jobs with a secondprofile in the print queue; (E) determining a change between the firstprofile and the second profile; (F) performing simulations to determineif the second set of at least two print jobs should be processed inaccordance with the first print job sequencing rule or a second printjob sequencing rule, the second print job sequencing rule dictating asecond print job sequence in a simulation of which the second set of atleast two print jobs can be processed, wherein the first print jobsequence is different than the second print lob sequence; (G)determining, using the simulations of (F), whether the second set of atleast two print jobs should be processed in accordance with the firstprint job sequencing rule or the second print job sequencing rule; and(H) in response to determining that the second set of at least two printjobs should be processed in accordance with the second print jobsequencing rule, reassigning the correspondence of the print queue fromthe first print job sequencing rule to the second print job sequencingrule.
 2. The method of claim 1, wherein said performing of (F) includes:(i) simulating processing of the second set of at least two print jobswith the cell and the first print job sequencing rule to obtain a firstprint job processing indicator; and (ii) simulating processing of thesecond set of at least two print jobs with the cell and the second printjob sequencing rule to obtain a second print job processing indicator.3. The method of claim 2, wherein said determining of (G) includescomparing the first print job processing indicator with the second printjob processing indicator.
 4. The method of claim 3, wherein said (G)includes determining whether the second set of at least two print jobsshould be processed in accordance with the first print job sequencingrule unless a difference between the first print job processingindicator and the second print job processing indicator exceeds aselected amount.
 5. The method of claim 2, wherein said performing of(F) includes corresponding the first print job processing indicator witha first average turnaround time, and the second print job processingindicator with a second average turnaround time.
 6. The method of claim5, wherein said (G) includes determining the second set of at least twoprint jobs should be processed in accordance with the first print jobsequencing rule unless the first average turnaround time differs fromthe second average turnaround time by a selected amount.
 7. The methodof claim 2, wherein said performing of (F) includes corresponding thefirst print job processing indicator with a first percentage value oflate jobs, and the second print job processing indicator with a secondpercentage value of late jobs.
 8. The method of claim 7, wherein said(G) includes determining the second set of at least two print jobsshould be processed in accordance with the first print job sequencingrule unless the first percentage value of late jobs differs from thesecond percentage value of late jobs by a selected amount.
 9. The methodof claim 1, further comprising:(I) performing (F) through (H) when orafter a selected condition occurs.
 10. The method of claim 9, in whichthe cell corresponds with a utilization, wherein said (I) includesperforming (F) through (H) when utilization at the cell exceeds aselected threshold.
 11. The method of claim 10, wherein said (H)includes performing (F) through (H) when one of device utilization anddevice user utilization at the cell exceeds the selected threshold. 12.The method of claim 9, wherein said (I) includes performing (F) through(H) when the second profile associated with the second set of at leasttwo print jobs is substantially different than the first profileassociated with the first set of at least two print jobs.
 13. The methodof claim 9, in which the cell is located in a print shop and the cell isone of a plurality of cells, wherein said (I) includes performing (D)through (H) in response to either (1) adding one or more cells to theplurality of cells, (2) deleting one or more cells from the plurality ofcells, or (3) reconfiguring at least one of the plurality of cells. 14.A method of ordering print jobs in a print queue, the print queue beingoperatively associated with a cell having one or more print processingdevices for processing print jobs, comprising: (A) storing one set of atleast two print jobs having a first profile in the print queue; (B)using a first print job sequencing rule to process the one set of atleast two print jobs with the cell, wherein the first print jobsequencing rule dictates a first print job sequence in which print jobsstored in the print queue are to be processed; (C) storing another setof at least two print jobs having a second profile in the print queue;(D) simulating processing of the other set of at least two print jobs inthe cell with the first sequencing rule to obtain a first print jobprocessing indicator; (E) determining if there is a change between thefirst profile and the second profile; (F) simulating processing of theother set of at least two print jobs in the cell based on a second printjob sequencing rule to obtain a second print job processing indicator,wherein the second print job sequencing rule dictates a second print jobsequence in which print jobs stored in the print queue are to beprocessed, and wherein the first print job sequence is different thanthe second print job sequence; (G) comparing the first print jobprocessing indicator with the second print job processing indicator; and(H) if a difference between the first and second print job processingindicators meets a threshold, reassigning the second print jobsequencing rule to the queue for processing the other set of at leasttwo print jobs with the cell.
 15. The method of claim 14, furthercomprising:(I) performing (C) through (H) when or after a selectedcondition occurs.
 16. The method of claim 15, wherein said (I) includesperforming (C) through (H) after a selected time interval hastranspired.
 17. The method of claim 15, in which the one set of at leasttwo print jobs corresponds with the first job profile having a firstattribute and the other set of at least two print jobs corresponds withthe second job profile having a second attribute, wherein said (I)includes performing (C) through (H) when the first attribute differsfrom the second attribute by a selected amount.
 18. The method of claim17, in which the first and second attributes correspond respectivelywith first and second job size related values, wherein said (I) includesperforming (F) through (H) when the first job size related value differsfrom the second job size related value by a selected amount.
 19. Themethod of claim 15, in which the cell corresponds with a utilizationlevel, wherein said (I) includes performing (C) through (H) when theutilization level exceeds a selected threshold.
 20. The method of claim19, wherein said (I) includes performing (C) through (H) when one ofdevice utilization and device user utilization at the cell exceeds theselected threshold.
 21. The method of claim 15, in which the cell islocated in a print shop and the cell is one of a plurality of cells,wherein said (I) includes performing (C) through (H) in response toeither (1) adding a cell to the plurality of cells, (2) deleting one ofthe plurality of cells, or (3) reconfiguring at least one of theplurality of cells.
 22. The method of claim 14, further comprising: (I)corresponding the first print job processing indicator with a firstaverage turnaround time, and the second print job processing indicatorwith a second average turnaround time.
 23. The method of claim 22,wherein said (H) includes processing the other set of at least two printjobs with the first print job sequencing rule unless the first averageturnaround time differs from the second average turnaround time by aselected amount.
 24. The method of claim 23, wherein said (H) includesprocessing the other set of at least two print jobs with the first printjob sequencing rule unless the first percentage value of late jobsdiffers from the second percentage value of late jobs by a selectedamount.
 25. The method of claim 14, further comprising: (I)corresponding the first print job processing indicator with a firstpercentage value of late jobs, and the second print job processingindicator with a second percentage value of late jobs.